Police are searching for the father of an infant who died Monday inside the family's southeast Houston apartment.

The mother of the month-old told Houston police nothing was out of the ordinary when she returned from work about 4 a.m. Monday to their home at the Las Villas Apartments on Broadway near the 610 South Loop.

She checked again about 6:30 a.m.

"The baby was still fine," said Sgt. Robert Torres, of HPD's homicide division.

She was awakened about 2 p.m. by her live-in boyfriend, who is the baby's father. They called 911 because their son was unresponsive, police said.

"They (Houston Fire Department paramedics) were unable to resuscitate the baby. The child was pronounced dead here at the scene," Torres said.

Detectives said there were no obvious signs of trauma but the cause of death wouldn't be known until Harris County medical examiners conduct an autopsy.

The father left the area before Houston police arrived. At this point, he is not considered a suspect.

"We do have to talk to him," Torres said.

The father is on probation for a family violence assault case with the child's mother listed as the victim, police said.